CA1314015C - Wall of plastics material with embedded connectors joined to electrodes - Google Patents
Wall of plastics material with embedded connectors joined to electrodesInfo
- Publication number
- CA1314015C CA1314015C CA000525400A CA525400A CA1314015C CA 1314015 C CA1314015 C CA 1314015C CA 000525400 A CA000525400 A CA 000525400A CA 525400 A CA525400 A CA 525400A CA 1314015 C CA1314015 C CA 1314015C
- Authority
- CA
- Canada
- Prior art keywords
- electrode
- wall
- electrically
- plastics material
- electrolytic cell
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
- C25B11/02—Electrodes; Manufacture thereof not otherwise provided for characterised by shape or form
- C25B11/03—Electrodes; Manufacture thereof not otherwise provided for characterised by shape or form perforated or foraminous
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
- C25B9/60—Constructional parts of cells
- C25B9/65—Means for supplying current; Electrode connections; Electric inter-cell connections
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
- Electrodes For Compound Or Non-Metal Manufacture (AREA)
Abstract
"Wall of Plastics Material With Embedded Connectors Joined to Electrodes"
An electrode which comprises a wall of plastics material, an electrically-conductive electrode surface on one side of the wall and displaced therefrom, an electrically-conductive electrode surface on the opposite side of the wall and displaced therefrom, at least one electrically-conductive connecting member in electrical contact with one of the electrode surfaces, at least one electrically-conductive connecting member in electrical contact with the other of the electrode surfaces, and in which the electrically-conductive connecting members are embedded in the wail of plastics material and are in electrical contact with each other.
Also, an electrolytic cell comprising a plurality of said electrodes, is disclosed.
An electrode which comprises a wall of plastics material, an electrically-conductive electrode surface on one side of the wall and displaced therefrom, an electrically-conductive electrode surface on the opposite side of the wall and displaced therefrom, at least one electrically-conductive connecting member in electrical contact with one of the electrode surfaces, at least one electrically-conductive connecting member in electrical contact with the other of the electrode surfaces, and in which the electrically-conductive connecting members are embedded in the wail of plastics material and are in electrical contact with each other.
Also, an electrolytic cell comprising a plurality of said electrodes, is disclosed.
Description
~ QM 33709 "Wall of Plastics Material With Embedded Conn_ctors Joined To Electrodes"
This invention relates to an electrode for u6e in an electrolytic cell, and in particular to a bipolar electrode for use in an electrolytic cell, although the invention i6 not limited to such bipolar electrodes.
Monopolar electrodes for use in electrolytic cells may take a variety of forms. ~hus, the electrode may consist of a single metal plate, which may be perforated, for example a punched plate, or it may consict of a metallic mesh, which may ~e woven or unwoven, or it may be a Qheet of expanded metal. The electrode may consist of a pair of ~uch plates, meshes or sheets which are spaced apart and which provide a pair of spaced apart outwardly-facing active electrcde surfaces, and the active electrode ~urfaces may have a coating of an electroconducting electro-catalytically-active material. An electrode o~ thi~ latter type provides a space for liquors in the electrode compartment~ of the cell, particularly when the active electrode surfaces are close to or in contact with a separator, that is with a hydraulically permeable diaphragm or a hydraulically Lmpermeable ion-exchange membrane positioned between an anode and an adjacent cathode. Ihe monopolar electrode must be provided with means for feeding electrical current to the electrode~
A bipolar electrode for u~e in an electrolytic cell mu~t fulfil a ~umber of ~eparate requirements.
Thu~, it must provide a barriex wall which in the electrolytic cell separates an anode compartment from an ad~acent cathode comparbment and which thus ~eparates the liquor in ~he anode compartment from ~he liquor in the cathode compartment. The bipolar electrode mu~t have an active anode ~urface on one ~ide of the barrier waIl and an active cathode ~urface on ` '::
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the opposite side of the barrier wall. These active anode surfaces and active cathode ~urfaces may have a coating of an electroconducting electrocatalytically-active material. It is preferred that the activè
anode surface, and the active cathode ~urface, each be displaced from the barrier wall in order to form a ~pace for the anolyte and catholyte liquors between the active anode surface and the barrier wall and between the active cathode surface and the barrier wall respectively. This is particularly desirable w~en the active anode surface and active cathode surface are close to or in contact with a separator positioned between an anode surface of one bipolar electrode and a cathode surface of an adjacent bipolar electrode. The bipolar electrode must also be provided with means for feeding electrical current from one electrode surface to the other electrode surface across the barrier wall.
There are many forms of such bipolar electrodesO
In GB Patent 1503799 there is described a bipolar electrode which comprises a barrier wall made of a titanium plate and an iron plate which plates have been explosion bonded together, a titanium anode displaced from and electrically connectad to the titanium plate of the barrier wall, and an iron cathode displaced from and electrically connected to the iron plate of the barrier wall, the iron cathode bein~
displaced from the iron plate of the barrier wall by a 30 ~ distance of at least 10 mm. The electrical connection between the titanium anode and the titanium plate of the barrier wall is provided by a plurality of titanium Rheets welded to the anode and to the plate of the barrier wall and positioned vertically therebetween.
Similarly, the electrical connection between the iron cathode and the iron plate of the barrier wall is provided by a plurality of iron 6heets welded to the cathode and to the plate of the barrier wall and positioned vertically therebetween.
US Patent 3755108 describes a bipolar electrolytic cell which comprises a plurality of bipolar units each of which comprises a metallic barrier wall, anodes mounted vertically on one side of the barrier wall, and cathodes mounted vertically on the opposite side of the barrier wall. In the electrolytic cell the bipolar units are so arranged that the anodes of one bipolar unit are interleaved with the cathodes of an adjacent bipolar unit, with a separator, which may be a hydraulically permeable diaphragm or a hydraulically impermeable ion-exchange membrane, positioned between adjacent anodes and cathodes.
Electrolytic cells have widespread applications, and they are used in particular on a large ~cale throughout the world in the production of chlorine and alkali metal hydroxide, or in the production of alkali metal chlorate or hypochlorite, by the electrolysis of aqueous alkali metal chloride solution.
Th electrolytic cell may be of the so-called tank type comprising, for example, a cathode box having a plurality of foraminate cathode fingers with an anode positioned in the gap between adjacent cathode ~ingers, or it may be of the filter press type and comprise a large number of alternating anode~ and cathodes, for ; example, fifty anodes alternating with fifty cathodes, although the cell may comprise even more anodes and 1 3 1 ~0 1 5 cathodes, for example up to one hundred and fifty alternating anodes and cathodes. The electrode of the present application is particularly suited for use in an electrolytic cell of the filter press type.
Where the electrolytic cell i5 used in the production of chlorine and alkali metal hydroxide the cell comprises a separator, which may be a hydraulically-permeable microporous diaphragm. Where aqueous alkali metal chloride solution is electrolysed in a cell containing a diaphragm the solution is charged to the anode compartments of the cell and chlorine produced in the electrolysis is removed therefrom, the solution passes through the diaphragm to the cathode compartments of the cell and hydrogen and aqueous alkali metal hydroxide 601ution produced by electrolysis are removed therefrom.
~ere the electrolytic cell contains an essentially hydraulically impermeable cation-exchange membrane aqueous alXali metal chloride ~olution is charged to the anode compartments of the c811 and chlorine produced in the electrolysis and depleted alkali metal chloride solution are removed from the anode compartments, alkali metal ions are transported across the membranes to the cathode compartments of the 2S cell to which water or dilute aqueous alkali metal hydroxide solution may be charged, and hydrogen and alkali metal hydroxide solution produced by the reaction of alkali metal ions with hydroxyl ions are removed from the cathode compartments of the cell.
Electrodes for use in electrolytic cell~, ~- including bipolar electrodes, are known w~ich comprise organic plastics material.
_5_ 1 31 4 01 5 U5 Patent 4141801 describes a fuel cell anode electrode made by pressing a paste of noble metal powder, graphite, and polytetrafluoroethylene onto a screen current collector and drying the electrode 80 formed.
US Patent 3600230 describes a gas electrode for u~e in a gas-depolarising current generating cell which comprises a metallic grid or screen, a porous conductive layer of a hydrophobic resinous material and conductive fibrous material in contact with one surface of the grid or screen, and a catalytically-active layer in contact with the outer ~urface of the porous conductive layer.
US Patent 4350608 describes a cathode formed by compressing a mixture of carbon black and polytetrafluoroethylene optionally onto a core of a metal mesh.
UK Patent application 2039954A describes a bipolar current collector which consists of a moulded aggregate of graphi$e and t~ermoplastic fluoropolymer.
The present invention relates to an electrode for use in an electrolytic cell which comprises a wall of an organic plastics material. The electrode of the invention is readily produced and, because it comprisPs a wall of a plastics material, it can readily be sealed by plastics processing techniques to a wall of an adjacent electrode, or to a frame-like gasket of a plastics material positioned between adjacent electrodes. Such techniques cannot, of course, be used to seal together adjacent electrodes of the types hereinbefore described which consist of a wall of metal or metals, for example, as in the electrodes described in GB Patent 1503799 and in US Patent 375S108. Furthermore, and unlike the electrodes consisting of a metal or metals hereinbeore described, the wall of plastics material is of light weight and may have some flexibility which also aids in sealing to a wall of an adjacent electrode, or to a gasket of a plastics material positioned between adjacent electrodes.
The present invention provides an electrode which comprises a wall of plastics material, an electrically-conductive electrode surace on one side of the wall and displaced therefrom, an electrically-conductive electrode surface on the opposite side of the wall and displaced therefrom, at least one electrically-conductive connecting member in electrical contact with one of the electrode surfaces, at least one electrically-conductive connecting member in electrical contact with the other of the electrode surfaces, and in which the electrically-conductive connecting members are embedded in the wall of plastics material and are in electrical contact with each ~5 other.
: Although use of the electrode in an electrolytic cell for the~production of chlorine and aqueous alkali metal hydroxide solution by the electrolysis of aqueous alkali metal chloride solution has been described it is to be understood that the electrode is not limited to use in an electrolytic cell for such electrolysis. By suitable choice of material~, and in particular of the ~ 3 1 4 0 1 5 wall of plastics material and of the electrode surfa`ces, it may be used in an electrolytic cell in which many different types of electrolyses may be effected.
The electrode of the invention may be a monopolar electrode or a bipolar electrode.
Where the electrode is a monopolar electrode it may be an anode or a cathode and should be provided with means of feeding electrical current to the electrode. The ~onopolar electrode, when installed in an electrolytic cell, should permit passage of liquid from one side of the wall of plastics material to the other, and in order to permit ~uch passage of liquor the wall may be perforated.
Where the electrode is a bipolar electrode the wall of plastics material should serve as a barrier wall which prevents pas~age of liquor from one side of the wall to the other, that is from an anode compartment on one side of the wall to a cathode compartment on the other side of the walI. In a bipolar electrode the electrode surface on one side of the wall serves as an anode and the electrode æur~ace on the oppo~ite ide of the wall serves as a cathode.
The invention also provides an electrolytic cell which comprises a plurality of electrodes as hereinbefore described. Where the electrode is a monopolar electrode the electrodes serve as anodes and cathodes, and optionally a æeparator may be positioned between each anode and adjacent cathode. Where the electrode is a bipolar electrode a separator may optionally be positioned between adjacent electrodes, - that iæ between an anode of one bipolar electrode and a cathode of an adjacent bipolar electrode. The electrolytic cell will be provided with means for charging electrolyte to the electrolytic cell and with means for removing products of electrolysis from the electrolytic cell.
The wall of the electrode is of a plastic material which will generally be electrically non-conductive. The wall is suitably in the form of a sheet of plastics material.
There is no particularly preferred thickness for the wall. It should of course be sufficiently thick as to provide a degree of structural integrity and~ in the case of a bipolar electrode, to act as a barrier between the liquors on opposite sides of the wall.
However, there is no particular advantage to be gained by having a thick wall, and in general a thicXne~s in the range 0.2 cm to 2 cm will suffice, although these thicknesses are not to be taken as being in any way limiting. The wall is suitably flexible and preferably resilient as this aids in fvrming leak tight 6eals when the electrode is inctalled in an electrolytic cell.
Unless the context dictates otherwise the anode surface and the cathode surface will hereafter be referred to as the electrode surfaces.
The electrode surfaces, which are electrically conductive and will generally be of metal, may take various forms. They may be non porous, e.g. in the form of a non-porous sheet, but more usually they will be foraminate, e.g. in the fo~m of a foraminate eheet.
The foraminate ~heet may, for example, be in the form of a perforated pl te, e.g. a punched plate, or a mesh, which may be a woven or unw~ven mesh, or an expanded substrate, e.g. an expanded metal.
' ~
The electrode surfaces of the electrode are each in electrical contact with at least one electrically-conductive connecting member. The purpo6e of these electrically-conductive connecting members is to conduct current from one electrode surface to the other, for example in a bipolar electrode from the anode surface of the electrode to the cathode surface of the electrode. In order to aid current distribution over the electrode surfaces it is preferred that the electrode surfaces are each in electrical contact with a plurality of electrically-conductive connecting members, which are ~paced apart and which are preferably substantially evenly spaced apart.
The electrically-conductive connecting members which are in electrical contact with the electrode surfaces may be in direct or indirect contact with each other. Thus, they may make indirect contact with each other by each being in electrical contact with a separate electrically conducting member, for example a sheet, e.g. a foraminate sheet, which may be of metal, embedded in the wall of plastics material. The use of such an embedded sheet aids in current distribution.
In the case of a monopolar electrode the embedded sheet may project beyond the edge of the wall of plastics material and thus provide a means by which electrical current may be fed to the electrode.
- The electrode of the invention may take a variety of different forms, and the electrode surfacP
and the electrically-conductive connecting member of the electrode may be of unitary construction or they may be of separate construction and electrically connected to each other.
-10- 13l~ol5 For example, the electrode surface and the associated electrically-conductive connecting members may be formed of a corrugated sheet, which i~ suitably foraminate, with the part of the sheet at or near to the peaks of the corrugations projecting from the wall of plastics material and serving as the electrode surface and the part of the sheet at or to near to the troughs of the corrugations serving a~ the connecting members and bein~ embedded in the wall of plastics material. The corrugations embedded in the wall of plastics material which are electrically connected to an electrode surface on one side of the wall are in electrical contact with the corrugations embedded in the wall which are electrically connected to the electrode surface on the opposite side of the wall. In order to provide a plurality of electrical contacts and to aid current distribution, and particularly where direct electrical contact is established between the corrugations of the sheets, the corrugated sheet providing one electrode surface may be positioned such that the corrugations are transverse to, for example substantially at right angles to, the corrugations of the corrugated sheet providing the opposite electrode surface. The electrode may be con~tructed ~y pressing corrugated sheets into the surface of a heat softened ; sheet of plastics material from opposite ides of the sheet until electrical contact, which may be direct or indirect, is established betwePn the corrugated sheets.
The ~heet of plastics material may then be allowed to harden.
The corrugated sheet is not necessarily of symmetrical fo~m, or even of substantially Rymmetrical form. For example, it may be unsymmetrical in that ,.
31~015 those parts of the corrugated sheet at or near the peaks thereof which project from the wall of plastics material and which ~erve as the electrode surface may co~er a relatively large area, and may be flat, and those parts of the corrugated sheet at or near the troughs thereof which are embedded in the wall of plastics material and which serve as the electrically-conductive connecting mem~ers may cover a relatively small area.
In another embodiment of the electrode of the invention the electrode surfaces comprise sheets, which are preferably foraminate and the electrically-conductive connecting members comprise a projection or projections upstanding from the sur~ace of each sheet.
The æheet preferably comprises a plurality of such projections on each sheetO The electrode may be constructed by pressing the projections attached to the sheets into the surface of a heat softened sheet of plastics material from opposite sides thereof until electrical contact, which may be direct or indirect, is establi~hed between the projections. In a preferred embodiment, which assists in obtaining good electrical contact between the projections embedded in the wall of plastics material, the wall of plastics material comprises an aperture or a plurality of apertures therein, and the electrode is constructed by positioning the pro~ections attached to the electrode surfaces through the apertures and in contact with each other and ~ealing the projections to each other, e.g.
by welding. The apertures in the wall are then sealed, e.g. by application of a plug of heat-softened plastics material, in order to maintain the electrode surfaces in the desired position r~lative to the wall of -12- ~31~015 plastics material, and in the case of a bipolar electr~de, in order that the wall may function as a barrier wall.
In the foregoi~g description of embodiments of the electr~de of the invention the electxically-conductive connecting members have been described as being of separate construction. However, the electrically-conductive connecting members attached to the electrode surfaces on opposite sides of the wall of plastics material may be of unitary construction. For example, the preferred embodiment of electrode previously described in which the wall comprises an aperture, or a plurality of apertures therein, and the electrode is constructed by positioning the projections attached to the electrode surfaces through the apertures and in contact with each other and ~ealing the projections to each other, e.g. by welding, may be constructed by positioning the projections a~tached to one of the electrode surfaces through the apertures in the barrier wall and sealing the projections into electrical contact with the opposite electrode surface, e.g. by welding. In this case ~he electrically-conductive connecting members attached originally to on~ electrode surface serve as the connecting members between the electrode surfaces.
~he electrically-conductive electrode surfaces are displaced fr~m the wall of plastics material. The amount o this displacement may be ~mall, or example, such that the electrode surfaces are merely slightly upstanding from the surface of the wall. However, it is preferred that the electrode surfaces be di~placed so as to leave a gap between the electrode ~urfaces and the wall which gap provides a space which serves as an electrode compartment. This i6 particularly necessary where the electrolytic cell comprises a separator which is near to or in contact with the anode and cathode surfaces of adjacent electrodes. The electrode surfaces may be displaced from the wall of plastics material by a distance of, for example 2 mm to 20 mm, although these specific displacements are not intended to be limiting.
In a preferred embodiment the projected area of the electrode surface is less than the projected area of the wall of plastics material such that, for example, in plan view the wall forms a frame-like section around the electrode surface. In the electrolytic cell frame-like gaskets, e.g. of plastics material, may be positioned on this frame-likç part of the wall and surround the electrode surfaces.
Alternatively, the wall of plastics material of the electrode and the gaskets may be of unitary construction in that the wall may have a greater ~hickness in the region of the frame-like part than in the part adjacent to the electrode surfaces. The frame-like part of the wall may extend to the plane of the electrode surfaces or extend beyond the p~ane of the electrode surfaces.
The wall of plastic~ material may be of a thermoplastic material, or of a thermosetting material, the nature of the material depending at least in part on the type of electrolysis which is to be effected in the electrolytic cell. The plastics material may be, for example, a polyolefin, e.g. polyethylene or polypropylene. It may be an aromatic polymer, e.g.
polystyrene, or a polymer containing ~uch aromatic ;
.
groups, e.g. an acrylonitrile-butadiene-styre~e polymer. It may be a halogenated polymer, for example a chlorine-containing polymer, e.g. polyvinyl chloride or chlorinated polyvinyl chloride, or a fluorine-containing polymer, e.g. polyvinyl fluoride, polyvinylidene fluoride, or polytetrafluoroethylene. , The plastics material may be an elastomer, for example, polybutadiene, polyisoprene, polychloroprene, an ethylene-propylene copolymer, an ethylene-propylene-diene copolymer, or an acrylonitrile-butadiene-styrene polymer aæ hereinbefore described.
Where the liquors in the electrolytic cell are particularly corrosive, for example in a cell for the electrolysis of aqueous alkali metal chloride solution, corrosion resistant plastics materials are preferred, ~or example, fluorine-containing plastics materials or plastics materials faced with or filled with such 1uorine-containing materials.
Examples of thermosetting plastics materials include polyester resins and epoxy resins.
The electrically-conducting electrode surfaces will generally be metallic, the nature of the metal depending on the type of electrolysis which i8 to be effected in the electrolytic cell. Wh~re aqueous alkali metal chloride solution is to be electolysed and the electrode surface is to function as an anode surface it is suitably made of, or at least has an active area of, a film forming metal or alloy, for example of zirconium, niobium, tungsten or tantalum.
T~le anode ~urface preferably has at least an active area of titanium, and the anode surface suitably carries a coatin~ of an electroconducting electrocatalytically-active material. The coating may .:
comprise one or more platinum group metals, that is piatinum, rhodium, iridium, xuthenium, osmium or palladium, and/or an oxide of one or more of these metals. The coating of platinum group metal and/or oxide may be present in admixture with one or more film-forming metal oxides, e.~. titanium dioxide, preferably in the form of a solid solution.
Electroconducting electrocatalytically-active materials for use as anode coatings in an electrolytic cell for the electrolysis of aqueous alkali metal chloride solution, and methods of application of such coatings, are well known in the art.
Where aqueous alkali metal chemical solution is to be electrolysed and the electrode surface is to function as a cathode the cathode surface is suitably made of, or at least has an acti~e area of iron or steel or other suitable metal, e.g. nicXel. The cathode surface may carry a coating of an electroconducting electrocatalytically-active material, ~0 e.g. a platinum group metal and/or oxide there~f, which lowers the hydrogen overvoltage of the cathode urface.
The electrolytic cell may be of the diaphragm or membrane type. In the aiaphragm type cell the separator positioned between an anode and an ad~acent cathode, or between an anode ~urface of a bipolar electrode and a cathode urface of adjacent bipolar electrode, to form separate anode compartments and cathode compartments in the cell are microporous and in use the electrolyte passes through the diaphragm from the anode compartments ~o the ca~hode compartments.
Thus, in the case where aqueous alkali metal chloride solu~ion i6 electrolysed ~he cell liquor which i8 produced comprises an aqueous solution of alkali metal :
chloride and alkali metal hydroxide. In the membrane type electrolytic cell the separators are es6entially hydraulically impermeable and in use ionic 6pecies are transported across the membranes between the S compartments of the cell. Thus, where the membrane is a cation-exchange membrane cations are tsan~ported across the membrane, and in the case where aqueou alXali metal ~hloride solutio~ i6 electrolysed the cell liquor comprises an aqueous solution of alkali metal hydroxide.
h~ere the separator to be used in the electrolytic cell i~ a microporous diaphragm the nature of the diaphragm will depend on the nature of the electrolyte which i~ to be ele~trolysed in the cell.
qhe diaphragm should be resistant ~o degradation by the electrolyte and by the products of electr~lysi~ and, where an aqueous solution of alkali metal chloride i~
to be electroly6ed, the diaphragm is suitably made of a fluorine-containing polymeric material a such ma~erial~ are generally resistant to degradation by the chlorine a~d alkali metal hydroxide s~lution pr~duced in the electroly~is. Preferably, the microporous diaphragm i8 made ~f polytetrafluoroethylene, although other materials which may be u~ed include, fsr exEmple, tetra~luoroethylene-hexafluoropropylene copolymers, vinylidene fluoride polymer and copolymers, a~d fluorinated ethylen2-propyl~ne c~polymers.
Suitable microporous diaphragms are ~hose descrlbed, for example, in UX Patent ~o 1503915 in which there i~ de~cribea a microporou~ ~iaphragm of polytetra-fluoroethylene having a micro~ruc~ure of ., nodes interconnected by fibrils, and in UK Patent ~o 1081046 in which there is deæcribed a microporous diaphragm produced by extracting a particulate filler from a sheet of polytetra1uoroethylene. Other suitable microporous diaphragms are described in the art.
Where the separator to be used in the cell is an ion-exchange membrane the nature of the membrane will also depend on the nature of the electrolyte which is to be electrolysed in the cell. The membrane æhould be resistant to degradation by the electrolyte and by the products of elctrolysis and, where an aqueous solution of alkali metal chloride i8 to be electrolysed, the membrane is suitably a cation-exchange membrane made of a fluorine--containing polymeric material containing cation-exchange groups, for example, sulphonic acid, carboxylic acid or phosphonic acid groups, or derivatives thereof, or a mixture of two or more such groups.
Suitable cation-exchange membranes are those described, for example, in UK Patents Nos 1184321, 1402920, 1406673, 1455070, 1497748, 1497749, 151~3g7 and 1531068.
The separators may be mounted on suitably shaped plates, which may act as sealing gaskets, positioned be~ween adjacent electrode~, or alternatively the separators may merely be held in position by clamping between adjacent electrodes.
The electrolytic cell may contain gaskets, which may be of the same plastics material as the wall of the electrode, or which may be of a different plastics material. The gaskets are preferably pliable and more preerably resilient.
In assembling the electrolytic cell the component parts may be positioned on tie rods and clamped together, or they may be sealed together, e.g.
by use of adhesives or by use of thermal welding, in the case where the plastics material is capable of being thermally welded.
The anode compartments of the electrolytic cell are provided with means for feeding electrolyte to the anode compartments, and with means for removing products of electrolysis from the anode compartments.
Similarly, the cathode compartments of the electrolytic cell are provided with means for removing products of electrolysis from the cathode compartments, and optionally with means for feeding water or other fluid to the cathode compartments.
For example, where the electrolytic cell is to be used in the electrolysis of aqueous alkali metal chloride solution the anode compartments are provided with means for feeding the aqueous alkali metal chloride solution thereto and with means for removing chlorine and optionally with means for removin~
depleted aqueous alkali metal chloride solution therefrom, and the cathode compartments are provided with means for removing hydrogen and cell liquor containing alkali metal hydroxide therefrom, and optionally, and if necessary, with means for feeding water or other fluids thereto. Although such means may be provided by æeparate pipes leading to or from each of the respective compartments such an arrangement would be unnecessarily complicated and cumbersome, and in a preferred embodiment of the electrolytic cell the wall of plastics material of the electrode, and of the separate gaskets, if present, comprises a plurality of openings, e.g. in a frame~like part thereof, which in the electrolytic cell define a plurality of compartments lengthwi~e of the cell which ~erve as headers from which, and to which, liquors may be passed. The liquors may be distributed from the headers to the electrode compartments, and to the headers from the electrode c~mpartments, by means of channels, e.g. slots, appropriately positio~ed in the wall of the plastics material of the electrode and/or in the gaskets, if present.
The invention will now be described with the aid of the following figures in which Figure 1 is an isometric exploded view of a bipolar electrode of the invention~
Figure 2 is a cross-sectional view in the direction A of the bipolar electrode of Figure 1, Figure 3 i~ an isometric exploded view of a bipolar electrode of the invention, Figure 4 is a cross-sectional view in the direction B of the bipolar electrode of Figure 3, Figure 5 is an i~ometric exploded view of a bipolar electrode of the invention, Figure 6 is a cross-sectional view in the direction C of the bipolar electrode of ~igure S, and Figure 7 is an i~ometric.partially exploded view of an electrolytic cell incorporating the bipolar electrode of Figure 4.
Referring to Figure~ 1 and 2 the bipolar electrode comprises a sheet 1 of thermoplastic polymer material w~ich ~erves a a barrier wall ~n the-electrode, a first corru~ated metallic 6heet 2 having perforation6 3, the peak~ 4 of which serve a~ an electrode ~urface and the trough~; 5 of which serve as ~' .
electrically conductive connecting mernbers, and a ~econd corrugated metallic fiheet 6 having perforations 7, the corrugations of ~heet 6 being positioned at right angles to those of the 6heet 2, and the peaks 8 of which ~erve as an electrode ~urface and the trough~
9 of which ~erve as electrically-conductive connecting members.
The bipolar electrode was as6embled by heat softening the sheet of thermoplastics material 1 and pressing the corrugated metallic sheets 2 and 6 into the heat-softened sheet 1 until the troughs 5 of sheet 2 and the troughs 9 of sheet 6 contact each other thereby forming the required electrical connection~.
As the corrugations of corrugated shee.t 2 are positioned at right angles to those of the corrugated sheet 6 a plurality of electrical connectionfi are formed. Finally, the ~heet of thermoplastic6 material 1 w~s ~ealed, by heat ~ealing, to a frame-Iike member 10 of the same thermoplastics material, the frame-like member 10, which i6 not shown in Figure 3, projecting from the plane of the ~heet 1 up to the planes of the peaks 4 and 8 of the corrugations of the corrugated metaIlic sheets 2 and 6 respectively.
Referring to Figures 3 and 4 the bipolar electrode comprises a metallic sheet 20 ha~in~
perforations 21 sandwiched between sheet~ ~2 and 23 of thermoplastic~ material. The sheet~ 20, 22 and 23 6erve as a barrier wall in ~he bipolar electrode. ~he electrode a1BO comprise~ a fir~t corrugated metallic sheet 24 havinq perforatio~s 25, ~e pea~ 26 of which serve as an electrode ~urface and the troughs 27 of which ~erve a~ electrically conductive connecting . ~ .
:, members, and a second corrugated metallic sheet 28 having perforations 29, the peaks 30 of w~ich serve as an electrode surface and the troughs 31 of which serve as electrically-conductive connecting members.
The bipolar electrode was assembled by heat softening the ~heets of thermoplastics ~aterial 22 and 23 and sandwiching the metallic sheet 20 between the sheets 22 and 23, and pressing the corrugated sheets 24 and 28 into the heat so~tened sheets 22 and 23 xespectively until the troughs 27 of sheet 24 and the troughs 31 of sheet 28 contact the sheet 20 thereby forming the required electrical connections. Finally, the sheets of thermoplastics material 22 and 23 were sealed, by heat sealing, to a frame-like member 32 of the same thermoplastics material, the frame-like member 32, which is not shown in Figure 3, projecting from the plane of the sheets 22 and 23 up to the planes of the peaks 26 and 30 of the corrugation6 of the corrugated metallic sheets 24 and 28 respectively.
Referring to Figures 5 and 6 the bipolar electrode comprises a sheet 40 of thermoplastics material, a metallic sheet 41 having perforations 42, and projections 4~ on one face of the sheet 41, and a metallic sheet 44 having perforations 45, and projections 46 on one face of the sheet 44. Prior to assembly of the electrode the ~heet 40 comprises openings 47.
The bipolar electrode was assembled by placing the projections 43 of metallic sheet 41 through the openings 47 in sheet 40 and sealing the projections 43 to the projections 46 on metallic sheet 44, e.g. by welding or by bra7ing. The openings 47 were then sealed by placing a plug 48 of thermopla~tics material in each of the openings 47 in order that the sheet 40 may form a barrier wall in the bipolar electrode.
Finally, the sheet of thermoplas~ics material 40 was sealed, by heat sealing, to a frame-like member 49 of the same thermoplastics material, the frame-like member 49, which is not shown in Figure 5, projecting from the plane of the sheet 40 up to the planes of the sheets 41 and 44 respectively.
In the electrolytic cell one of the metallic sheets of the bipolar electrode will serve as an anode and the other as a cathode and the surface of each sheet may have a coating of a suitable electrocatalytically-active electroconducting material.
Titanium is a suitable metal for an anode sheet and nickel is a suitable metal for a cathode ~heet.
In the embodiment illustrated in Figure 7 the bipolar electrode in the electrolytic cell is of the type described with reference to Figures 3 and 4.
The electrolytic cell~comprises a frame-like member 60 of an acrylonitrile-butadiene-styrene polymeric material (ABS) having a central opening in which a bipolar electrode 61 is positioned.
The frame-like member 60 has four openings 62, 63, 64, 65 which serve as locations for tie rods used in assembly of the electrolytic cell, as hereinafter described.
~he frame-like member 60 comprises a horizontally disposed opening 66 through the thickness of the frame-like member 60 and a vertically disposed channel 67 which leads from the opening 66 to one face of the bipolar electrode 61, and a hori~ontally disposed opening 68 through the thickness of the -23- 131~015 frame-liXe member 60 and a vertically di~posed channel (not shown) w~lich leads from the opening 68 to the oppo~ite face of the bipolar electrode 61.
Similarly, the frame-like member 60 compri6es four horizontally disposed openings 69, 70, 71, 72 throu~h the thickness of the frame-like member 60 and four channels 73, 74, 75, 76 respectively as~ociated with said openings, the channels 74, 75 leading from one face of the bipolar electrode 61 to the opening6 70, 71 respectively, and the channels 73, 76 leading from the opposite face of the bipolar electrode 61 to the openings 69, 72 respectively.
The electrolytic cell also comprises a frame-like member 77 of ABS polymeric material having a central opening in which a cation-exchange membrane 78 is positioned. The membrane 78 has an area slightly larger than the central openinq in the frame-like ~ember 77 and may be affixed thereto by mean~ of an ad~esive.
~ ternatively, the membrane 78 may be ~andwiched between a pair of frame-like section6 which are bonded together to form the frame-like member 77. The frame-like member 77 comprises four openings 79, 80, 81 (one not shown), corresponding in position to the openings 62, 63, 64, 65 in the frame-liXe member 60 and which serve a6 locations for tie rods used in a6sembly of the electrolytic celi, and six horizontally di~po~ed openin~s 82, 83, 84, 85 (two not ~hown) corre~ponding in position to the opening~ 69, 70, 71, 72, 66 and 68 in the frame-like member 60.
In assembling the electrolytic cell a frame-like member 60 i~ positioned on four tie tod6 through the opening~ 62, 63, 64, 65 and a ~ace of ~h~ member 60 i~
.
.
~, . . ~ , .
-24- 1 31 ~01 5 coated with an adhesive comprising ABS polymeric material in an organic solvent, e.g. perchlorethylene.
A frame-like member 77 is then positioned on the tie rods and contacted with the adhesive-coated face of the frame-like member 60. The opposite face of the frame-like member 77 is similarly coated with adhesive and another frame-like member 60 is positioned on the tie rods and contacted with the adhesive coated face of the frame-like member 77. In this way a ~tack of frame-like members 60 comprising bipolar electrodes 61 and frame-like members 77 comprising cation-exchange membranes is built up, the stack is held in compression until the frame-like members are firmly bonded together, and the tie rods are removed.
In the electrolytic cell the horizontally disposed openings 66, 68, 69, 70, 71, 72 in the frame-like members 60 and the corresponding openings (two not shown) 82, 83, 84 and 85 in the frame-like members 77 together form channels lengthwise of the cell through which, respectively aqueous alkali metal chloride solution may be charged to the anode compartments of the cell, water or dilute aqueous alkaii metal hyd.roxide ~olution may be charged to the cathode compartment of the cell, hydrogen produced by electrolysis may be removed from the cathode compartments, chlorine produced by electrolysis may be removed from the anode compartments, depleted aqueous alkali metal chloride solution may be removed from the anode compartments, and aqueous alkali metal hydroxide solution produced by electrolysis may be removed from the cathode compartments.
Assembly of the electrolytic cell i6 completed by sealin~ end plates (not shown) to each end of the cell, completing electrical connections, and co~necting to appropriate headers he channels of which the openings 66, 68, 69, 70, 71, 72 form a part.
In operation in the electrolysis of aqueous alkali metal chloride solution the solution is charged to the anode c~mpartments of the electrolytic cell through the lengthwise channel of which opening 66 forms a part and through vertically disposed channel 67, and depleted alkali metal chloride solution and chlorine produced in the electrolysis are removed from the anode compartments, respectively, through the channel 75 and the lengthwise channel of which opening 71 forms a part, and through channel 74 and the lengthwise channel of which opening 70 forms a part.
Water or dilute alkali metal hydroxide ~olution is charged to the cathode compartments of the electrolytic cell through the lengthwise channel of which opening 6~ forms a part and through a vertically disposed channel (not shown), and alkali metal hydroxide solution and hydrogen produced in the electrolysis are removed from the cathode compartments, respectively, through the channel 76 and the lengthwise channel o which opening 72 forms a part, and through channel 73 and the lengthwise channel of which opening 69 forms a part.
This invention relates to an electrode for u6e in an electrolytic cell, and in particular to a bipolar electrode for use in an electrolytic cell, although the invention i6 not limited to such bipolar electrodes.
Monopolar electrodes for use in electrolytic cells may take a variety of forms. ~hus, the electrode may consist of a single metal plate, which may be perforated, for example a punched plate, or it may consict of a metallic mesh, which may ~e woven or unwoven, or it may be a Qheet of expanded metal. The electrode may consist of a pair of ~uch plates, meshes or sheets which are spaced apart and which provide a pair of spaced apart outwardly-facing active electrcde surfaces, and the active electrode ~urfaces may have a coating of an electroconducting electro-catalytically-active material. An electrode o~ thi~ latter type provides a space for liquors in the electrode compartment~ of the cell, particularly when the active electrode surfaces are close to or in contact with a separator, that is with a hydraulically permeable diaphragm or a hydraulically Lmpermeable ion-exchange membrane positioned between an anode and an adjacent cathode. Ihe monopolar electrode must be provided with means for feeding electrical current to the electrode~
A bipolar electrode for u~e in an electrolytic cell mu~t fulfil a ~umber of ~eparate requirements.
Thu~, it must provide a barriex wall which in the electrolytic cell separates an anode compartment from an ad~acent cathode comparbment and which thus ~eparates the liquor in ~he anode compartment from ~he liquor in the cathode compartment. The bipolar electrode mu~t have an active anode ~urface on one ~ide of the barrier waIl and an active cathode ~urface on ` '::
"
` :
the opposite side of the barrier wall. These active anode surfaces and active cathode ~urfaces may have a coating of an electroconducting electrocatalytically-active material. It is preferred that the activè
anode surface, and the active cathode ~urface, each be displaced from the barrier wall in order to form a ~pace for the anolyte and catholyte liquors between the active anode surface and the barrier wall and between the active cathode surface and the barrier wall respectively. This is particularly desirable w~en the active anode surface and active cathode surface are close to or in contact with a separator positioned between an anode surface of one bipolar electrode and a cathode surface of an adjacent bipolar electrode. The bipolar electrode must also be provided with means for feeding electrical current from one electrode surface to the other electrode surface across the barrier wall.
There are many forms of such bipolar electrodesO
In GB Patent 1503799 there is described a bipolar electrode which comprises a barrier wall made of a titanium plate and an iron plate which plates have been explosion bonded together, a titanium anode displaced from and electrically connectad to the titanium plate of the barrier wall, and an iron cathode displaced from and electrically connected to the iron plate of the barrier wall, the iron cathode bein~
displaced from the iron plate of the barrier wall by a 30 ~ distance of at least 10 mm. The electrical connection between the titanium anode and the titanium plate of the barrier wall is provided by a plurality of titanium Rheets welded to the anode and to the plate of the barrier wall and positioned vertically therebetween.
Similarly, the electrical connection between the iron cathode and the iron plate of the barrier wall is provided by a plurality of iron 6heets welded to the cathode and to the plate of the barrier wall and positioned vertically therebetween.
US Patent 3755108 describes a bipolar electrolytic cell which comprises a plurality of bipolar units each of which comprises a metallic barrier wall, anodes mounted vertically on one side of the barrier wall, and cathodes mounted vertically on the opposite side of the barrier wall. In the electrolytic cell the bipolar units are so arranged that the anodes of one bipolar unit are interleaved with the cathodes of an adjacent bipolar unit, with a separator, which may be a hydraulically permeable diaphragm or a hydraulically impermeable ion-exchange membrane, positioned between adjacent anodes and cathodes.
Electrolytic cells have widespread applications, and they are used in particular on a large ~cale throughout the world in the production of chlorine and alkali metal hydroxide, or in the production of alkali metal chlorate or hypochlorite, by the electrolysis of aqueous alkali metal chloride solution.
Th electrolytic cell may be of the so-called tank type comprising, for example, a cathode box having a plurality of foraminate cathode fingers with an anode positioned in the gap between adjacent cathode ~ingers, or it may be of the filter press type and comprise a large number of alternating anode~ and cathodes, for ; example, fifty anodes alternating with fifty cathodes, although the cell may comprise even more anodes and 1 3 1 ~0 1 5 cathodes, for example up to one hundred and fifty alternating anodes and cathodes. The electrode of the present application is particularly suited for use in an electrolytic cell of the filter press type.
Where the electrolytic cell i5 used in the production of chlorine and alkali metal hydroxide the cell comprises a separator, which may be a hydraulically-permeable microporous diaphragm. Where aqueous alkali metal chloride solution is electrolysed in a cell containing a diaphragm the solution is charged to the anode compartments of the cell and chlorine produced in the electrolysis is removed therefrom, the solution passes through the diaphragm to the cathode compartments of the cell and hydrogen and aqueous alkali metal hydroxide 601ution produced by electrolysis are removed therefrom.
~ere the electrolytic cell contains an essentially hydraulically impermeable cation-exchange membrane aqueous alXali metal chloride ~olution is charged to the anode compartments of the c811 and chlorine produced in the electrolysis and depleted alkali metal chloride solution are removed from the anode compartments, alkali metal ions are transported across the membranes to the cathode compartments of the 2S cell to which water or dilute aqueous alkali metal hydroxide solution may be charged, and hydrogen and alkali metal hydroxide solution produced by the reaction of alkali metal ions with hydroxyl ions are removed from the cathode compartments of the cell.
Electrodes for use in electrolytic cell~, ~- including bipolar electrodes, are known w~ich comprise organic plastics material.
_5_ 1 31 4 01 5 U5 Patent 4141801 describes a fuel cell anode electrode made by pressing a paste of noble metal powder, graphite, and polytetrafluoroethylene onto a screen current collector and drying the electrode 80 formed.
US Patent 3600230 describes a gas electrode for u~e in a gas-depolarising current generating cell which comprises a metallic grid or screen, a porous conductive layer of a hydrophobic resinous material and conductive fibrous material in contact with one surface of the grid or screen, and a catalytically-active layer in contact with the outer ~urface of the porous conductive layer.
US Patent 4350608 describes a cathode formed by compressing a mixture of carbon black and polytetrafluoroethylene optionally onto a core of a metal mesh.
UK Patent application 2039954A describes a bipolar current collector which consists of a moulded aggregate of graphi$e and t~ermoplastic fluoropolymer.
The present invention relates to an electrode for use in an electrolytic cell which comprises a wall of an organic plastics material. The electrode of the invention is readily produced and, because it comprisPs a wall of a plastics material, it can readily be sealed by plastics processing techniques to a wall of an adjacent electrode, or to a frame-like gasket of a plastics material positioned between adjacent electrodes. Such techniques cannot, of course, be used to seal together adjacent electrodes of the types hereinbefore described which consist of a wall of metal or metals, for example, as in the electrodes described in GB Patent 1503799 and in US Patent 375S108. Furthermore, and unlike the electrodes consisting of a metal or metals hereinbeore described, the wall of plastics material is of light weight and may have some flexibility which also aids in sealing to a wall of an adjacent electrode, or to a gasket of a plastics material positioned between adjacent electrodes.
The present invention provides an electrode which comprises a wall of plastics material, an electrically-conductive electrode surace on one side of the wall and displaced therefrom, an electrically-conductive electrode surface on the opposite side of the wall and displaced therefrom, at least one electrically-conductive connecting member in electrical contact with one of the electrode surfaces, at least one electrically-conductive connecting member in electrical contact with the other of the electrode surfaces, and in which the electrically-conductive connecting members are embedded in the wall of plastics material and are in electrical contact with each ~5 other.
: Although use of the electrode in an electrolytic cell for the~production of chlorine and aqueous alkali metal hydroxide solution by the electrolysis of aqueous alkali metal chloride solution has been described it is to be understood that the electrode is not limited to use in an electrolytic cell for such electrolysis. By suitable choice of material~, and in particular of the ~ 3 1 4 0 1 5 wall of plastics material and of the electrode surfa`ces, it may be used in an electrolytic cell in which many different types of electrolyses may be effected.
The electrode of the invention may be a monopolar electrode or a bipolar electrode.
Where the electrode is a monopolar electrode it may be an anode or a cathode and should be provided with means of feeding electrical current to the electrode. The ~onopolar electrode, when installed in an electrolytic cell, should permit passage of liquid from one side of the wall of plastics material to the other, and in order to permit ~uch passage of liquor the wall may be perforated.
Where the electrode is a bipolar electrode the wall of plastics material should serve as a barrier wall which prevents pas~age of liquor from one side of the wall to the other, that is from an anode compartment on one side of the wall to a cathode compartment on the other side of the walI. In a bipolar electrode the electrode surface on one side of the wall serves as an anode and the electrode æur~ace on the oppo~ite ide of the wall serves as a cathode.
The invention also provides an electrolytic cell which comprises a plurality of electrodes as hereinbefore described. Where the electrode is a monopolar electrode the electrodes serve as anodes and cathodes, and optionally a æeparator may be positioned between each anode and adjacent cathode. Where the electrode is a bipolar electrode a separator may optionally be positioned between adjacent electrodes, - that iæ between an anode of one bipolar electrode and a cathode of an adjacent bipolar electrode. The electrolytic cell will be provided with means for charging electrolyte to the electrolytic cell and with means for removing products of electrolysis from the electrolytic cell.
The wall of the electrode is of a plastic material which will generally be electrically non-conductive. The wall is suitably in the form of a sheet of plastics material.
There is no particularly preferred thickness for the wall. It should of course be sufficiently thick as to provide a degree of structural integrity and~ in the case of a bipolar electrode, to act as a barrier between the liquors on opposite sides of the wall.
However, there is no particular advantage to be gained by having a thick wall, and in general a thicXne~s in the range 0.2 cm to 2 cm will suffice, although these thicknesses are not to be taken as being in any way limiting. The wall is suitably flexible and preferably resilient as this aids in fvrming leak tight 6eals when the electrode is inctalled in an electrolytic cell.
Unless the context dictates otherwise the anode surface and the cathode surface will hereafter be referred to as the electrode surfaces.
The electrode surfaces, which are electrically conductive and will generally be of metal, may take various forms. They may be non porous, e.g. in the form of a non-porous sheet, but more usually they will be foraminate, e.g. in the fo~m of a foraminate eheet.
The foraminate ~heet may, for example, be in the form of a perforated pl te, e.g. a punched plate, or a mesh, which may be a woven or unw~ven mesh, or an expanded substrate, e.g. an expanded metal.
' ~
The electrode surfaces of the electrode are each in electrical contact with at least one electrically-conductive connecting member. The purpo6e of these electrically-conductive connecting members is to conduct current from one electrode surface to the other, for example in a bipolar electrode from the anode surface of the electrode to the cathode surface of the electrode. In order to aid current distribution over the electrode surfaces it is preferred that the electrode surfaces are each in electrical contact with a plurality of electrically-conductive connecting members, which are ~paced apart and which are preferably substantially evenly spaced apart.
The electrically-conductive connecting members which are in electrical contact with the electrode surfaces may be in direct or indirect contact with each other. Thus, they may make indirect contact with each other by each being in electrical contact with a separate electrically conducting member, for example a sheet, e.g. a foraminate sheet, which may be of metal, embedded in the wall of plastics material. The use of such an embedded sheet aids in current distribution.
In the case of a monopolar electrode the embedded sheet may project beyond the edge of the wall of plastics material and thus provide a means by which electrical current may be fed to the electrode.
- The electrode of the invention may take a variety of different forms, and the electrode surfacP
and the electrically-conductive connecting member of the electrode may be of unitary construction or they may be of separate construction and electrically connected to each other.
-10- 13l~ol5 For example, the electrode surface and the associated electrically-conductive connecting members may be formed of a corrugated sheet, which i~ suitably foraminate, with the part of the sheet at or near to the peaks of the corrugations projecting from the wall of plastics material and serving as the electrode surface and the part of the sheet at or to near to the troughs of the corrugations serving a~ the connecting members and bein~ embedded in the wall of plastics material. The corrugations embedded in the wall of plastics material which are electrically connected to an electrode surface on one side of the wall are in electrical contact with the corrugations embedded in the wall which are electrically connected to the electrode surface on the opposite side of the wall. In order to provide a plurality of electrical contacts and to aid current distribution, and particularly where direct electrical contact is established between the corrugations of the sheets, the corrugated sheet providing one electrode surface may be positioned such that the corrugations are transverse to, for example substantially at right angles to, the corrugations of the corrugated sheet providing the opposite electrode surface. The electrode may be con~tructed ~y pressing corrugated sheets into the surface of a heat softened ; sheet of plastics material from opposite ides of the sheet until electrical contact, which may be direct or indirect, is established betwePn the corrugated sheets.
The ~heet of plastics material may then be allowed to harden.
The corrugated sheet is not necessarily of symmetrical fo~m, or even of substantially Rymmetrical form. For example, it may be unsymmetrical in that ,.
31~015 those parts of the corrugated sheet at or near the peaks thereof which project from the wall of plastics material and which ~erve as the electrode surface may co~er a relatively large area, and may be flat, and those parts of the corrugated sheet at or near the troughs thereof which are embedded in the wall of plastics material and which serve as the electrically-conductive connecting mem~ers may cover a relatively small area.
In another embodiment of the electrode of the invention the electrode surfaces comprise sheets, which are preferably foraminate and the electrically-conductive connecting members comprise a projection or projections upstanding from the sur~ace of each sheet.
The æheet preferably comprises a plurality of such projections on each sheetO The electrode may be constructed by pressing the projections attached to the sheets into the surface of a heat softened sheet of plastics material from opposite sides thereof until electrical contact, which may be direct or indirect, is establi~hed between the projections. In a preferred embodiment, which assists in obtaining good electrical contact between the projections embedded in the wall of plastics material, the wall of plastics material comprises an aperture or a plurality of apertures therein, and the electrode is constructed by positioning the pro~ections attached to the electrode surfaces through the apertures and in contact with each other and ~ealing the projections to each other, e.g.
by welding. The apertures in the wall are then sealed, e.g. by application of a plug of heat-softened plastics material, in order to maintain the electrode surfaces in the desired position r~lative to the wall of -12- ~31~015 plastics material, and in the case of a bipolar electr~de, in order that the wall may function as a barrier wall.
In the foregoi~g description of embodiments of the electr~de of the invention the electxically-conductive connecting members have been described as being of separate construction. However, the electrically-conductive connecting members attached to the electrode surfaces on opposite sides of the wall of plastics material may be of unitary construction. For example, the preferred embodiment of electrode previously described in which the wall comprises an aperture, or a plurality of apertures therein, and the electrode is constructed by positioning the projections attached to the electrode surfaces through the apertures and in contact with each other and ~ealing the projections to each other, e.g. by welding, may be constructed by positioning the projections a~tached to one of the electrode surfaces through the apertures in the barrier wall and sealing the projections into electrical contact with the opposite electrode surface, e.g. by welding. In this case ~he electrically-conductive connecting members attached originally to on~ electrode surface serve as the connecting members between the electrode surfaces.
~he electrically-conductive electrode surfaces are displaced fr~m the wall of plastics material. The amount o this displacement may be ~mall, or example, such that the electrode surfaces are merely slightly upstanding from the surface of the wall. However, it is preferred that the electrode surfaces be di~placed so as to leave a gap between the electrode ~urfaces and the wall which gap provides a space which serves as an electrode compartment. This i6 particularly necessary where the electrolytic cell comprises a separator which is near to or in contact with the anode and cathode surfaces of adjacent electrodes. The electrode surfaces may be displaced from the wall of plastics material by a distance of, for example 2 mm to 20 mm, although these specific displacements are not intended to be limiting.
In a preferred embodiment the projected area of the electrode surface is less than the projected area of the wall of plastics material such that, for example, in plan view the wall forms a frame-like section around the electrode surface. In the electrolytic cell frame-like gaskets, e.g. of plastics material, may be positioned on this frame-likç part of the wall and surround the electrode surfaces.
Alternatively, the wall of plastics material of the electrode and the gaskets may be of unitary construction in that the wall may have a greater ~hickness in the region of the frame-like part than in the part adjacent to the electrode surfaces. The frame-like part of the wall may extend to the plane of the electrode surfaces or extend beyond the p~ane of the electrode surfaces.
The wall of plastic~ material may be of a thermoplastic material, or of a thermosetting material, the nature of the material depending at least in part on the type of electrolysis which is to be effected in the electrolytic cell. The plastics material may be, for example, a polyolefin, e.g. polyethylene or polypropylene. It may be an aromatic polymer, e.g.
polystyrene, or a polymer containing ~uch aromatic ;
.
groups, e.g. an acrylonitrile-butadiene-styre~e polymer. It may be a halogenated polymer, for example a chlorine-containing polymer, e.g. polyvinyl chloride or chlorinated polyvinyl chloride, or a fluorine-containing polymer, e.g. polyvinyl fluoride, polyvinylidene fluoride, or polytetrafluoroethylene. , The plastics material may be an elastomer, for example, polybutadiene, polyisoprene, polychloroprene, an ethylene-propylene copolymer, an ethylene-propylene-diene copolymer, or an acrylonitrile-butadiene-styrene polymer aæ hereinbefore described.
Where the liquors in the electrolytic cell are particularly corrosive, for example in a cell for the electrolysis of aqueous alkali metal chloride solution, corrosion resistant plastics materials are preferred, ~or example, fluorine-containing plastics materials or plastics materials faced with or filled with such 1uorine-containing materials.
Examples of thermosetting plastics materials include polyester resins and epoxy resins.
The electrically-conducting electrode surfaces will generally be metallic, the nature of the metal depending on the type of electrolysis which i8 to be effected in the electrolytic cell. Wh~re aqueous alkali metal chloride solution is to be electolysed and the electrode surface is to function as an anode surface it is suitably made of, or at least has an active area of, a film forming metal or alloy, for example of zirconium, niobium, tungsten or tantalum.
T~le anode ~urface preferably has at least an active area of titanium, and the anode surface suitably carries a coatin~ of an electroconducting electrocatalytically-active material. The coating may .:
comprise one or more platinum group metals, that is piatinum, rhodium, iridium, xuthenium, osmium or palladium, and/or an oxide of one or more of these metals. The coating of platinum group metal and/or oxide may be present in admixture with one or more film-forming metal oxides, e.~. titanium dioxide, preferably in the form of a solid solution.
Electroconducting electrocatalytically-active materials for use as anode coatings in an electrolytic cell for the electrolysis of aqueous alkali metal chloride solution, and methods of application of such coatings, are well known in the art.
Where aqueous alkali metal chemical solution is to be electrolysed and the electrode surface is to function as a cathode the cathode surface is suitably made of, or at least has an acti~e area of iron or steel or other suitable metal, e.g. nicXel. The cathode surface may carry a coating of an electroconducting electrocatalytically-active material, ~0 e.g. a platinum group metal and/or oxide there~f, which lowers the hydrogen overvoltage of the cathode urface.
The electrolytic cell may be of the diaphragm or membrane type. In the aiaphragm type cell the separator positioned between an anode and an ad~acent cathode, or between an anode ~urface of a bipolar electrode and a cathode urface of adjacent bipolar electrode, to form separate anode compartments and cathode compartments in the cell are microporous and in use the electrolyte passes through the diaphragm from the anode compartments ~o the ca~hode compartments.
Thus, in the case where aqueous alkali metal chloride solu~ion i6 electrolysed ~he cell liquor which i8 produced comprises an aqueous solution of alkali metal :
chloride and alkali metal hydroxide. In the membrane type electrolytic cell the separators are es6entially hydraulically impermeable and in use ionic 6pecies are transported across the membranes between the S compartments of the cell. Thus, where the membrane is a cation-exchange membrane cations are tsan~ported across the membrane, and in the case where aqueou alXali metal ~hloride solutio~ i6 electrolysed the cell liquor comprises an aqueous solution of alkali metal hydroxide.
h~ere the separator to be used in the electrolytic cell i~ a microporous diaphragm the nature of the diaphragm will depend on the nature of the electrolyte which i~ to be ele~trolysed in the cell.
qhe diaphragm should be resistant ~o degradation by the electrolyte and by the products of electr~lysi~ and, where an aqueous solution of alkali metal chloride i~
to be electroly6ed, the diaphragm is suitably made of a fluorine-containing polymeric material a such ma~erial~ are generally resistant to degradation by the chlorine a~d alkali metal hydroxide s~lution pr~duced in the electroly~is. Preferably, the microporous diaphragm i8 made ~f polytetrafluoroethylene, although other materials which may be u~ed include, fsr exEmple, tetra~luoroethylene-hexafluoropropylene copolymers, vinylidene fluoride polymer and copolymers, a~d fluorinated ethylen2-propyl~ne c~polymers.
Suitable microporous diaphragms are ~hose descrlbed, for example, in UX Patent ~o 1503915 in which there i~ de~cribea a microporou~ ~iaphragm of polytetra-fluoroethylene having a micro~ruc~ure of ., nodes interconnected by fibrils, and in UK Patent ~o 1081046 in which there is deæcribed a microporous diaphragm produced by extracting a particulate filler from a sheet of polytetra1uoroethylene. Other suitable microporous diaphragms are described in the art.
Where the separator to be used in the cell is an ion-exchange membrane the nature of the membrane will also depend on the nature of the electrolyte which is to be electrolysed in the cell. The membrane æhould be resistant to degradation by the electrolyte and by the products of elctrolysis and, where an aqueous solution of alkali metal chloride i8 to be electrolysed, the membrane is suitably a cation-exchange membrane made of a fluorine--containing polymeric material containing cation-exchange groups, for example, sulphonic acid, carboxylic acid or phosphonic acid groups, or derivatives thereof, or a mixture of two or more such groups.
Suitable cation-exchange membranes are those described, for example, in UK Patents Nos 1184321, 1402920, 1406673, 1455070, 1497748, 1497749, 151~3g7 and 1531068.
The separators may be mounted on suitably shaped plates, which may act as sealing gaskets, positioned be~ween adjacent electrode~, or alternatively the separators may merely be held in position by clamping between adjacent electrodes.
The electrolytic cell may contain gaskets, which may be of the same plastics material as the wall of the electrode, or which may be of a different plastics material. The gaskets are preferably pliable and more preerably resilient.
In assembling the electrolytic cell the component parts may be positioned on tie rods and clamped together, or they may be sealed together, e.g.
by use of adhesives or by use of thermal welding, in the case where the plastics material is capable of being thermally welded.
The anode compartments of the electrolytic cell are provided with means for feeding electrolyte to the anode compartments, and with means for removing products of electrolysis from the anode compartments.
Similarly, the cathode compartments of the electrolytic cell are provided with means for removing products of electrolysis from the cathode compartments, and optionally with means for feeding water or other fluid to the cathode compartments.
For example, where the electrolytic cell is to be used in the electrolysis of aqueous alkali metal chloride solution the anode compartments are provided with means for feeding the aqueous alkali metal chloride solution thereto and with means for removing chlorine and optionally with means for removin~
depleted aqueous alkali metal chloride solution therefrom, and the cathode compartments are provided with means for removing hydrogen and cell liquor containing alkali metal hydroxide therefrom, and optionally, and if necessary, with means for feeding water or other fluids thereto. Although such means may be provided by æeparate pipes leading to or from each of the respective compartments such an arrangement would be unnecessarily complicated and cumbersome, and in a preferred embodiment of the electrolytic cell the wall of plastics material of the electrode, and of the separate gaskets, if present, comprises a plurality of openings, e.g. in a frame~like part thereof, which in the electrolytic cell define a plurality of compartments lengthwi~e of the cell which ~erve as headers from which, and to which, liquors may be passed. The liquors may be distributed from the headers to the electrode compartments, and to the headers from the electrode c~mpartments, by means of channels, e.g. slots, appropriately positio~ed in the wall of the plastics material of the electrode and/or in the gaskets, if present.
The invention will now be described with the aid of the following figures in which Figure 1 is an isometric exploded view of a bipolar electrode of the invention~
Figure 2 is a cross-sectional view in the direction A of the bipolar electrode of Figure 1, Figure 3 i~ an isometric exploded view of a bipolar electrode of the invention, Figure 4 is a cross-sectional view in the direction B of the bipolar electrode of Figure 3, Figure 5 is an i~ometric exploded view of a bipolar electrode of the invention, Figure 6 is a cross-sectional view in the direction C of the bipolar electrode of ~igure S, and Figure 7 is an i~ometric.partially exploded view of an electrolytic cell incorporating the bipolar electrode of Figure 4.
Referring to Figure~ 1 and 2 the bipolar electrode comprises a sheet 1 of thermoplastic polymer material w~ich ~erves a a barrier wall ~n the-electrode, a first corru~ated metallic 6heet 2 having perforation6 3, the peak~ 4 of which serve a~ an electrode ~urface and the trough~; 5 of which serve as ~' .
electrically conductive connecting mernbers, and a ~econd corrugated metallic fiheet 6 having perforations 7, the corrugations of ~heet 6 being positioned at right angles to those of the 6heet 2, and the peaks 8 of which ~erve as an electrode ~urface and the trough~
9 of which ~erve as electrically-conductive connecting members.
The bipolar electrode was as6embled by heat softening the sheet of thermoplastics material 1 and pressing the corrugated metallic sheets 2 and 6 into the heat-softened sheet 1 until the troughs 5 of sheet 2 and the troughs 9 of sheet 6 contact each other thereby forming the required electrical connection~.
As the corrugations of corrugated shee.t 2 are positioned at right angles to those of the corrugated sheet 6 a plurality of electrical connectionfi are formed. Finally, the ~heet of thermoplastic6 material 1 w~s ~ealed, by heat ~ealing, to a frame-Iike member 10 of the same thermoplastics material, the frame-like member 10, which i6 not shown in Figure 3, projecting from the plane of the ~heet 1 up to the planes of the peaks 4 and 8 of the corrugations of the corrugated metaIlic sheets 2 and 6 respectively.
Referring to Figures 3 and 4 the bipolar electrode comprises a metallic sheet 20 ha~in~
perforations 21 sandwiched between sheet~ ~2 and 23 of thermoplastic~ material. The sheet~ 20, 22 and 23 6erve as a barrier wall in ~he bipolar electrode. ~he electrode a1BO comprise~ a fir~t corrugated metallic sheet 24 havinq perforatio~s 25, ~e pea~ 26 of which serve as an electrode ~urface and the troughs 27 of which ~erve a~ electrically conductive connecting . ~ .
:, members, and a second corrugated metallic sheet 28 having perforations 29, the peaks 30 of w~ich serve as an electrode surface and the troughs 31 of which serve as electrically-conductive connecting members.
The bipolar electrode was assembled by heat softening the ~heets of thermoplastics ~aterial 22 and 23 and sandwiching the metallic sheet 20 between the sheets 22 and 23, and pressing the corrugated sheets 24 and 28 into the heat so~tened sheets 22 and 23 xespectively until the troughs 27 of sheet 24 and the troughs 31 of sheet 28 contact the sheet 20 thereby forming the required electrical connections. Finally, the sheets of thermoplastics material 22 and 23 were sealed, by heat sealing, to a frame-like member 32 of the same thermoplastics material, the frame-like member 32, which is not shown in Figure 3, projecting from the plane of the sheets 22 and 23 up to the planes of the peaks 26 and 30 of the corrugation6 of the corrugated metallic sheets 24 and 28 respectively.
Referring to Figures 5 and 6 the bipolar electrode comprises a sheet 40 of thermoplastics material, a metallic sheet 41 having perforations 42, and projections 4~ on one face of the sheet 41, and a metallic sheet 44 having perforations 45, and projections 46 on one face of the sheet 44. Prior to assembly of the electrode the ~heet 40 comprises openings 47.
The bipolar electrode was assembled by placing the projections 43 of metallic sheet 41 through the openings 47 in sheet 40 and sealing the projections 43 to the projections 46 on metallic sheet 44, e.g. by welding or by bra7ing. The openings 47 were then sealed by placing a plug 48 of thermopla~tics material in each of the openings 47 in order that the sheet 40 may form a barrier wall in the bipolar electrode.
Finally, the sheet of thermoplas~ics material 40 was sealed, by heat sealing, to a frame-like member 49 of the same thermoplastics material, the frame-like member 49, which is not shown in Figure 5, projecting from the plane of the sheet 40 up to the planes of the sheets 41 and 44 respectively.
In the electrolytic cell one of the metallic sheets of the bipolar electrode will serve as an anode and the other as a cathode and the surface of each sheet may have a coating of a suitable electrocatalytically-active electroconducting material.
Titanium is a suitable metal for an anode sheet and nickel is a suitable metal for a cathode ~heet.
In the embodiment illustrated in Figure 7 the bipolar electrode in the electrolytic cell is of the type described with reference to Figures 3 and 4.
The electrolytic cell~comprises a frame-like member 60 of an acrylonitrile-butadiene-styrene polymeric material (ABS) having a central opening in which a bipolar electrode 61 is positioned.
The frame-like member 60 has four openings 62, 63, 64, 65 which serve as locations for tie rods used in assembly of the electrolytic cell, as hereinafter described.
~he frame-like member 60 comprises a horizontally disposed opening 66 through the thickness of the frame-like member 60 and a vertically disposed channel 67 which leads from the opening 66 to one face of the bipolar electrode 61, and a hori~ontally disposed opening 68 through the thickness of the -23- 131~015 frame-liXe member 60 and a vertically di~posed channel (not shown) w~lich leads from the opening 68 to the oppo~ite face of the bipolar electrode 61.
Similarly, the frame-like member 60 compri6es four horizontally disposed openings 69, 70, 71, 72 throu~h the thickness of the frame-like member 60 and four channels 73, 74, 75, 76 respectively as~ociated with said openings, the channels 74, 75 leading from one face of the bipolar electrode 61 to the opening6 70, 71 respectively, and the channels 73, 76 leading from the opposite face of the bipolar electrode 61 to the openings 69, 72 respectively.
The electrolytic cell also comprises a frame-like member 77 of ABS polymeric material having a central opening in which a cation-exchange membrane 78 is positioned. The membrane 78 has an area slightly larger than the central openinq in the frame-like ~ember 77 and may be affixed thereto by mean~ of an ad~esive.
~ ternatively, the membrane 78 may be ~andwiched between a pair of frame-like section6 which are bonded together to form the frame-like member 77. The frame-like member 77 comprises four openings 79, 80, 81 (one not shown), corresponding in position to the openings 62, 63, 64, 65 in the frame-liXe member 60 and which serve a6 locations for tie rods used in a6sembly of the electrolytic celi, and six horizontally di~po~ed openin~s 82, 83, 84, 85 (two not ~hown) corre~ponding in position to the opening~ 69, 70, 71, 72, 66 and 68 in the frame-like member 60.
In assembling the electrolytic cell a frame-like member 60 i~ positioned on four tie tod6 through the opening~ 62, 63, 64, 65 and a ~ace of ~h~ member 60 i~
.
.
~, . . ~ , .
-24- 1 31 ~01 5 coated with an adhesive comprising ABS polymeric material in an organic solvent, e.g. perchlorethylene.
A frame-like member 77 is then positioned on the tie rods and contacted with the adhesive-coated face of the frame-like member 60. The opposite face of the frame-like member 77 is similarly coated with adhesive and another frame-like member 60 is positioned on the tie rods and contacted with the adhesive coated face of the frame-like member 77. In this way a ~tack of frame-like members 60 comprising bipolar electrodes 61 and frame-like members 77 comprising cation-exchange membranes is built up, the stack is held in compression until the frame-like members are firmly bonded together, and the tie rods are removed.
In the electrolytic cell the horizontally disposed openings 66, 68, 69, 70, 71, 72 in the frame-like members 60 and the corresponding openings (two not shown) 82, 83, 84 and 85 in the frame-like members 77 together form channels lengthwise of the cell through which, respectively aqueous alkali metal chloride solution may be charged to the anode compartments of the cell, water or dilute aqueous alkaii metal hyd.roxide ~olution may be charged to the cathode compartment of the cell, hydrogen produced by electrolysis may be removed from the cathode compartments, chlorine produced by electrolysis may be removed from the anode compartments, depleted aqueous alkali metal chloride solution may be removed from the anode compartments, and aqueous alkali metal hydroxide solution produced by electrolysis may be removed from the cathode compartments.
Assembly of the electrolytic cell i6 completed by sealin~ end plates (not shown) to each end of the cell, completing electrical connections, and co~necting to appropriate headers he channels of which the openings 66, 68, 69, 70, 71, 72 form a part.
In operation in the electrolysis of aqueous alkali metal chloride solution the solution is charged to the anode c~mpartments of the electrolytic cell through the lengthwise channel of which opening 66 forms a part and through vertically disposed channel 67, and depleted alkali metal chloride solution and chlorine produced in the electrolysis are removed from the anode compartments, respectively, through the channel 75 and the lengthwise channel of which opening 71 forms a part, and through channel 74 and the lengthwise channel of which opening 70 forms a part.
Water or dilute alkali metal hydroxide ~olution is charged to the cathode compartments of the electrolytic cell through the lengthwise channel of which opening 6~ forms a part and through a vertically disposed channel (not shown), and alkali metal hydroxide solution and hydrogen produced in the electrolysis are removed from the cathode compartments, respectively, through the channel 76 and the lengthwise channel o which opening 72 forms a part, and through channel 73 and the lengthwise channel of which opening 69 forms a part.
Claims (24)
1. An electrode which comprises a wall of plastics material, an electrically-conductive electrode surface on one side of the wall and displaced therefrom, an electrically-conductive electrode surface on the opposite side of the wall and displaced therefrom, at least one electrically-conductive connecting member in electrical contact at one end thereof with one of the electrode surfaces, at least one electrically-conductive connecting member in electrical contact at one end thereof with the other of the electrode surfaces, and in which the ends of the electrically-conductive connecting members opposite to the ends thereof which are in electrical contact with the electrode surfaces are embedded in the wall of the plastics material and make electrical contact with each other within the wall of plastics material.
2. An electrode as claimed in Claim 1 which is monopolar and in which the wall is perforated.
3. An electrode as claimed in Claim 1 which is bipolar and in which the wall is a barrier wall.
4. An electrode as claimed in any one of Claims 1 to 3 in which the wall is made of an electrically non-conductive plastics material.
5. An electrode as claimed in any one of Claims 1 to 3 in which the wall is in the form of a sheet.
6. An electrode as claimed in any one of Claims 1 to 3 in which the wall is flexible.
7. An electrode as claimed in any one of Claims 1 to 3 in which the electrically-conductive electrode surfaces are metallic.
8. An electrode as claimed in any one of Claims 1 to 3 in which the electrode surfaces are foraminate.
9. An electrode as claimed in any one of Claims 1 to 3 in which the electrode surfaces are foraminate sheets.
10. An electrode as claimed in Claim 1 in which the electrode surfaces are in electrical contact with a plurality of electrically-conductive connecting members.
11. An electrode as claimed in any one of Claims 1 and 10 in which the electrically-conductive connecting members are in electrical contact with a metallic sheet embedded in the wall of plastics material.
12. An electrode as claimed in Claim 1 in which the electrode surfaces and the associated electrically-conductive connecting members are formed of corrugated sheets.
13. An electrode as claimed in Claim 12 in which the corrugations of one corrugated sheet which provides one electrode surface are positioned transverse to the corrugations of the corrugated sheet which provides the opposite electrode surface.
14. An electrode as claimed in Claim 1 in which both electrode surfaces comprise a sheet and the electrically-conductive connecting members comprise a projection or projections upstanding from the surface of the sheet.
15. An electrode as claimed in Claim 14 in which the wall of plastics material comprises an aperture or a plurality of apertures therein, and the electrode is constructed by positioning the projections attached to the electrode surfaces in the apertures and in contact with each other, sealing the projections to each other, and sealing the apertures in the wall.
16. An electrode as claimed in Claim 14 in which the area of the electrode surface projecting from the wall of plastic material is less than the area of the wall of plastic material.
Case No. QM 33709
Case No. QM 33709
17. An electrode as claimed in Claim 16 in which the wall includes a frame-like section around the electrode surfaces.
18. An electrode as claimed in Claim 17 in which the frame-like section of the wall extends at least to the plane of the electrode surfaces.
19. An electrode as claimed in any one of Claims 1, 14 and 15 in which the plastics material is a thermoplastic material.
20. An electrode as claimed in any one of Claims 1, 14 and 15 in which the plastics material is an elastomer.
21. An electrode as claimed in any one of Claims 1, 10 and 14 in which one of the electrode surfaces is made of a film-forming metal or alloy and the other of the electrode surfaces is made of iron or nickel.
22. The use of an electrode as described in Claim 1, 10 or 14 in an electrolytic cell.
23. The use of an electrode as described in Claim 1, 2 or 14 in an electrolytic cell, said electrode being a monopolar electrode and said electrolytic cell comprising anodes and cathodes and a separator between each anode and adjacent cathode.
24. The use of an electrode as described in Claim 1, 3 or 14 in an electrolytic cell, said electrode being a bipolar electrode comprising an anode and cathode and said electrolytic cell comprising a separator positioned between an anode of a bipolar electrode and a cathode of an adjacent bipolar electrode.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB858530893A GB8530893D0 (en) | 1985-12-16 | 1985-12-16 | Electrode |
| GB8530893 | 1985-12-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1314015C true CA1314015C (en) | 1993-03-02 |
Family
ID=10589807
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000525400A Expired - Fee Related CA1314015C (en) | 1985-12-16 | 1986-12-16 | Wall of plastics material with embedded connectors joined to electrodes |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US4746415A (en) |
| EP (1) | EP0229473B1 (en) |
| JP (1) | JPS62156284A (en) |
| AU (1) | AU585104B2 (en) |
| CA (1) | CA1314015C (en) |
| DE (1) | DE3675364D1 (en) |
| GB (2) | GB8530893D0 (en) |
| IN (1) | IN169374B (en) |
| ZA (1) | ZA869109B (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8620341D0 (en) * | 1986-08-21 | 1986-10-01 | Hydrogen Systems Nv | Bipolar plate-system |
| DE3886108D1 (en) * | 1987-07-01 | 1994-01-20 | Deutsche Aerospace | Process for producing a composite of a cermet layer and a porous metal layer on one or both sides of the cermet layer as a diaphragm with an electrode (s). |
| US5013414A (en) * | 1989-04-19 | 1991-05-07 | The Dow Chemical Company | Electrode structure for an electrolytic cell and electrolytic process used therein |
| SE465966B (en) * | 1989-07-14 | 1991-11-25 | Permascand Ab | ELECTRIC FOR ELECTRIC LIGHTING, PROCEDURE FOR ITS MANUFACTURING AND APPLICATION OF THE ELECTRODE |
| US5254233A (en) * | 1990-02-15 | 1993-10-19 | Asahi Glass Company Ltd. | Monopolar ion exchange membrane electrolytic cell assembly |
| US5221452A (en) * | 1990-02-15 | 1993-06-22 | Asahi Glass Company Ltd. | Monopolar ion exchange membrane electrolytic cell assembly |
| CN1019590B (en) * | 1990-09-03 | 1992-12-23 | 张学明 | High-efficient electrolytic apparatus for producing hydrogen and oxygen |
| EP0521386B1 (en) * | 1991-06-26 | 1996-09-04 | CHLORINE ENGINEERS CORP., Ltd. | Electrolyzer and its production |
| ITMI940853A1 (en) * | 1994-05-03 | 1995-11-03 | Nora Permelec S P A Ora De Nora S P A De | ELECTROLIZERS FOR THE PRODUCTION OF SODIUM HYPOCHLORITE AND SODIUM CHLORATE EQUIPPED WITH IMPROVED ELECTRODES |
| CA2333859A1 (en) * | 2001-02-01 | 2002-08-01 | Donald W. Kirk | Electrochemical cell stacks |
| AT411465B (en) * | 2001-07-24 | 2004-01-26 | Prior Eng Ag | Stripping cathode, for precipitating metals from solution in electrolytic cell, comprises parallel metal sheets sandwiching insulant layer |
| CN1771354A (en) * | 2003-04-29 | 2006-05-10 | 贝克特股份有限公司 | Bipolar plate comprising metal wire |
| DE102005008664A1 (en) * | 2005-02-25 | 2006-08-31 | Bayer Technology Services Gmbh | Tempered chamber filter plate or pressing-washing plate, for use in filter press, especially for drying filter cakes, has heating or cooling body with corrugated elements forming cavity for tempering medium |
| KR200423499Y1 (en) * | 2006-03-09 | 2006-08-09 | 주식회사 에너지마스타 | apparatus of generation oxygen/hydrogen gas |
| US9657400B2 (en) * | 2008-06-10 | 2017-05-23 | General Electric Company | Electrolyzer assembly method and system |
| WO2014075741A1 (en) * | 2012-11-19 | 2014-05-22 | Tina Energy Systems S.L. | Pem-type electrolyzer stack for operation at high pressure |
| JP2019532477A (en) * | 2016-10-21 | 2019-11-07 | ナントエナジー，インク． | Corrugated fuel electrode |
| EP4092164A1 (en) * | 2021-05-17 | 2022-11-23 | Siemens Energy Global GmbH & Co. KG | Pressure equipment with support structure device |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1536290A (en) * | 1967-06-21 | 1968-08-16 | Improvements in electrolysers intended in particular for the production of pure gases such as oxygen and hydrogen | |
| US3600230A (en) * | 1969-09-22 | 1971-08-17 | Yardney International Corp | Gas-depolarized cell with hydrophobic-resin-containing cathode |
| US3755108A (en) * | 1971-08-12 | 1973-08-28 | Ppg Industries Inc | Method of producing uniform anolyte heads in the individual cells of a bipolar electrolyzer |
| BE793045A (en) * | 1971-12-21 | 1973-06-20 | Rhone Progil | BIPOLAR ELECTRODES |
| BE793122A (en) * | 1971-12-22 | 1973-06-21 | Rhone Progil | DISMOUNTABLE BIPOLAR ELECTRODES |
| US3873437A (en) * | 1972-11-09 | 1975-03-25 | Diamond Shamrock Corp | Electrode assembly for multipolar electrolytic cells |
| US3849279A (en) * | 1973-12-17 | 1974-11-19 | Basf Wyandotte Corp | Apparatus for sealing mechanical connection at bipolar barrier sheet |
| US3950239A (en) * | 1974-07-24 | 1976-04-13 | Hooker Chemicals & Plastics Corporation | Electrical connector for bipolar electrodes |
| JPS5232866B2 (en) * | 1974-10-09 | 1977-08-24 | ||
| US4085027A (en) * | 1975-01-29 | 1978-04-18 | Kerr-Mcgee Chemical Corporation | Hybrid bipolar electrode |
| US4115236A (en) * | 1977-12-01 | 1978-09-19 | Allied Chemical Corporation | Cell connector for bipolar electrolyzer |
| US4141801A (en) * | 1977-12-15 | 1979-02-27 | The United States Of America As Represented By The Secretary Of The Army | Fuel cell anode electrode, method of making the fuel cell anode electrode, and fuel cell containing the fuel cell anode electrode |
| US4350608A (en) * | 1978-04-24 | 1982-09-21 | Diamond Shamrock Corporation | Oxygen cathode for alkali-halide electrolysis and method of making same |
| US4214969A (en) * | 1979-01-02 | 1980-07-29 | General Electric Company | Low cost bipolar current collector-separator for electrochemical cells |
| ATE30175T1 (en) * | 1981-11-24 | 1987-10-15 | Ici Plc | ELECTRODE STRUCTURE FOR USE IN A FILTER PRESS TYPE ELECTROLYTIC CELL. |
-
1985
- 1985-12-16 GB GB858530893A patent/GB8530893D0/en active Pending
-
1986
- 1986-11-27 DE DE8686309278T patent/DE3675364D1/en not_active Expired - Fee Related
- 1986-11-27 EP EP86309278A patent/EP0229473B1/en not_active Expired - Lifetime
- 1986-11-27 GB GB868628413A patent/GB8628413D0/en active Pending
- 1986-12-02 ZA ZA869109A patent/ZA869109B/en unknown
- 1986-12-02 US US06/936,910 patent/US4746415A/en not_active Expired - Fee Related
- 1986-12-03 IN IN1063/DEL/86A patent/IN169374B/en unknown
- 1986-12-08 AU AU66198/86A patent/AU585104B2/en not_active Ceased
- 1986-12-16 CA CA000525400A patent/CA1314015C/en not_active Expired - Fee Related
- 1986-12-16 JP JP61297861A patent/JPS62156284A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62156284A (en) | 1987-07-11 |
| EP0229473A1 (en) | 1987-07-22 |
| GB8628413D0 (en) | 1986-12-31 |
| GB8530893D0 (en) | 1986-01-29 |
| US4746415A (en) | 1988-05-24 |
| AU6619886A (en) | 1987-06-18 |
| IN169374B (en) | 1991-10-05 |
| AU585104B2 (en) | 1989-06-08 |
| DE3675364D1 (en) | 1990-12-06 |
| EP0229473B1 (en) | 1990-10-31 |
| ZA869109B (en) | 1987-08-26 |
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| Date | Code | Title | Description |
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| MKLA | Lapsed |